<?php


function msubstr($str, $start=0, $length, $charset="utf-8", $suffix=false){

	if(function_exists("mb_substr")){

		if($suffix)

			return mb_substr($str, $start, $length, $charset)."...";

		else

			return mb_substr($str, $start, $length, $charset);

	}elseif(function_exists('iconv_substr')) {

		if($suffix)

			return iconv_substr($str,$start,$length,$charset)."...";

		else

			return iconv_substr($str,$start,$length,$charset);

	}

	$re['utf-8'] = "/[x01-x7f]|[xc2-xdf][x80-xbf]|[xe0-xef][x80-xbf]{2}|[xf0-xff][x80-xbf]{3}/";

	$re['gb2312'] = "/[x01-x7f]|[xb0-xf7][xa0-xfe]/";

	$re['gbk'] = "/[x01-x7f]|[x81-xfe][x40-xfe]/";

	$re['big5'] = "/[x01-x7f]|[x81-xfe]([x40-x7e]|xa1-xfe])/";

	preg_match_all($re[$charset], $str, $match);

	$slice = join("",array_slice($match[0], $start, $length));

	if($suffix) return $slice."…";

	return $slice;

}